The invention relates generally to airborne alerting systems, and more specifically to an airborne alerting system to provide separation assurance during closely-spaced parallel approaches.
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. The following notice applies to the software and data as described below and in the drawings hereto: Copyright(copyright) 1998, Honeywell, Inc., All Rights Reserved.
Air travel is becoming increasingly prevalent in both business and leisure travel. As a result, airports are experiencing increasing amounts of air traffic. Accordingly, air traffic control needs to become more efficient to safely bring in more aircraft with limited resources, i.e., runways.
Currently, airports that have aircraft landing on runways that are less than 4,300 feet apart suffer a serious reduction in capacity when Instrument Approach Procedures (IAPs) are implemented due to weather conditions. The weather conditions under which IAPs commence are not as severe as Instrument Meteorological Conditions, defined by the U.S. Federal Aviation Administration (FAA) to be ceilings less than 1,000 feet or visibility less than 3 miles. For example, a midwestern airport adopts IAP when the ceiling is less than 3,200 feet or when visibility is less than 8 miles.
For a number of years, the quest for capacity improvements to make Airport Arrival Rates (AAR) robust to weather changes has been pursued with vigor. Recently, a system called the Precision Runway Monitor (PRM) has been developed by the FAA, which gives the controllers high-update surveillance capability and an alerting function to determine if aircraft are blundering and need to perform a xe2x80x9cbreakoutxe2x80x9d maneuver to avoid a potential collision. PRM applies to runways with spacings, centerline to centerline, of at least 3,400 feet.
But airports are not always afforded the luxury of runway spacings of at least 3,400 feet. Busier airports tend to be associated with large metropolitan areas where real estate is at a premium. Runway spacing may be as low as 2,500 feet or even lower in many airports.
As will be seen from the above concerns, there exists a need for an airborne alerting system to provide capacity improvements, especially for the case of runway spacing below 3,400 feet. The above mentioned problems with AAR and other problems are addressed by the present invention and will be understood by reading and studying the following specification.
The invention provides a method of assuring separation of aircraft during approach. In one embodiment, tracking information for aircraft is obtained through data transmissions by the aircraft. An observer is alerted if the tracking information indicates at least one of the aircraft is blundering from an assigned approach.
Another embodiment of the invention provides a method of assuring separation of aircraft between a first aircraft and other aircraft. The method includes determining whether the other aircraft are transmitting tracking information. Aircraft transmitting the tracking information are armed aircraft. The tracking information comprises position and velocity, wherein the position is defined in a geographic coordinate system. The method further includes obtaining the tracking information from each armed aircraft, applying separation assurance algorithms to the tracking information for each armed aircraft within a predetermined zone relative to the first aircraft, and alerting an observer when the separation assurance algorithms are indicative of a threat to the first aircraft.
A further embodiment of the invention includes an alerting system. The alerting system includes a track file. The track file contains data including latitude data, longitude data and altitude data for each aircraft providing ADS-B position reports to support the alerting function associated with closely-spaced parallel approaches. The data are defined in a geographic coordinate system. The alerting system generates alerts to an observer when a comparison of the positions and trajectories are indicative of a threat to the observer.
The various embodiments of the invention may be implemented on computer systems and provide an improvement over the Precision Runway Monitor system because the embodiments of the invention are applicable to runways spaced as closely as 2,500 feet. While the concepts of the invention are applicable to runways spaced closer than 2,500 feet, current FAA rules associated with Wake Vortex protection require that two runways be treated as a single runway if they are closer than 2,500 feet. The airborne alerting system further provides pilots proximity awareness of the adjacent traffic. The airborne alerting system allows for minimal ground infrastructure, reducing installation and operational costs. It further reduces air traffic controller personnel requirements, since PRM requires two dedicated controllers and the system embodied in the invention does not. By leveraging existing TCAS II protocols, pilot training is minimized. And the airborne alerting system embodied by the invention also facilitates quicker alerting of pilots to potential problems, given that alerting comes directly from an on-board system and not via an air traffic controller over the radio. Subsequently, safety is increased and/or false alarms are reduced.